Is it permissible to give needy siblings from zakat and vows, and is the one who undertakes her brother's education rewarded, and is she sinful for concealing that from her husband?

If your brothers and sisters do not have enough for their sustenance and housing, it is permissible for you to give them from your Zakat (definition) al-mal and your vows, for they are more deserving of charity, as Allah says: "Zakah expenditures are only for the poor and for the needy..." As for your father, it is not permissible for you to give him from Zakat if his maintenance is obligatory upon you, unless you are unable to provide for him. A mature woman has the right to dispose of her money in permissible matters without her husband's permission, and she is not obliged to inform him of this.